The effectiveness of comprehensive geriatric assessment intervention for older people in outpatient setting: a systematic review / meta-analysis

Abstract

Introduction

Comprehensive geriatric assessment (CGA) is a multidisciplinary diagnostic and treatment process that identifies a frail older person’s medical, psychosocial, and functional limitations. The effectiveness of CGA in patients admitted to hospitals is well known, but it is still unclear whether those benefits translate to the outpatient setting. Therefore, this study aims to assess the effectiveness of CGA in the hospital outpatient setting.

Methods

We collected randomized clinical trials comparing CGA and usual care in the outpatient setting for older patients (aged 60 years and above). We used a combination of the keywords and their synonyms in several databases: PubMed, EMBASE Proquest, and the clinical trial registry. Risk of bias (RoB) assessment was done using RoB 2 from Cochrane. GRADE assessment for outcome mortality and hospitalization was also done.

Result

We found seven articles with a total of 3,254 subjects undergoing CGA in the outpatient clinic. The implementation of CGA is highly varied from center to center. Low-quality evidence demonstrated that CGA did not significantly affect all-cause mortality, patient satisfaction, hospitalization, functional status of basic and instrumental activities of daily living, cognitive, and cost. Very low-quality evidence showed favorable quality of life in CGA group at 3 and 12 months, as reported by individual studies. No difference was found in all studies relating to the risk of hospitalization.

Conclusion

CGA is a complex intervention and is highly dependent on context. Therefore, a robust conclusion is challenging to make due to the different practices and measurement tools used in the studies. Further research using a guideline for hospital outpatient CGA may be beneficial.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-025-06048-8.

Introduction

The global population aged over 60 is rapidly increasing, with projections estimating 2.1 billion individuals in this age group by 2050, doubling the 1 billion recorded in 2019 [1]. This demographic growth will bring a surge in health issues specific to older adults, collectively referred to as geriatric syndromes. These syndromes include cognitive impairment, delirium, incontinence, malnutrition, falls, gait disorders, pressure ulcers, sleep disorders, sensory deficits, fatigue, and dizziness [2]. Due to the complexity of these conditions, clinicians must conduct thorough assessments to effectively manage them and prevent or delay complications.

Comprehensive Geriatric Assessment (CGA) provides a multidisciplinary approach to diagnosing and treating frail older adults. This process identifies medical, psychosocial, and functional limitations to develop a coordinated plan that maximizes overall health and well-being as individuals age [3]. Research has established the effectiveness of CGA for hospitalized patients. A systematic review by Ellis et al. revealed that older patients receiving inpatient CGA were more likely to remain in their homes, maintain better functional performance, and face a reduced risk of institutionalization [4]. However, the benefits of CGA in non-hospital settings remain less clear [5].

This study aims to investigate the effectiveness of CGA specifically in hospital outpatient settings. Previous research suggests that outpatient CGA may improve function, mobility, survival, and delay the progression to frailty [6–8]. In response, we conducted a systematic review to compare the outcomes of outpatient CGA with usual care, focusing on its impact on survival, function, and quality of life. Usual care is define as medical and social care without geriatric assessment. We also aim to examine the types of CGA used and their associated outcomes.

Methods

This systematic review compared comprehensive geriatric assessment (CGA) to usual care in managing older patients (aged 60+) in hospital outpatient settings. The study was clinically registered prospectively in the International Prospective Register of Systematic Reviews (PROSPERO) under submission ID CRD42022339402. The manuscript followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines [9].

Criteria for considering studies for this review

Types of studies

Only randomized controlled trials (RCT) were considered for inclusion.

Types of participants

Older patients were defined as individuals aged 60 years and above, regardless of frailty status (e.g., robust, prefrail, or frail).

Types of interventions

CGA is a multidisciplinary diagnostic and therapeutic process that comprehensively assesses physical, psychological, functional, and socio-economic dimensions to develop individualized treatment plans [10]. This review compared CGA to usual care (non-CGA interventions).

Type of setting

This review focused solely on CGA implemented in hospital outpatient clinics (outpatient assessment service or OAS), excluding home assessment service (HAS) and hospital home assessment service (HHAS) [11].

Outcomes

Primary outcome

• All-cause mortality.

• Quality of life assessed using validated instruments.

• Patient satisfaction assessed using validated instruments.

Secondary outcome

• Hospitalization.

• Functional status in daily living measured using any validated instruments to asses the ability to perform basic and instrumental activities of daily living.

• Cognitive function.

• Cost and cost-effectiveness.

Search method for the identification of studies

We used a combination of keywords and synonyms across multiple databases, including PubMed, EMBASE, and ProQuest. A high-sensitivity filter was applied to identify RCTs. No restrictions were applied regarding language or publication year.

Ongoing studies were identified via trial registries, including ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP), and the EU Clinical Trials Register. Reference lists of identified studies were also hand-searched for additional relevant trials or reviews. The complete search strategy was provided in the appendix.

Data collection

Selection of studies

Pairs of authors independently screened titles and abstracts, followed by full-text assessments based on predefined inclusion criteria. Discrepancies were resolved through discussion or by a third reviewer. The study selection process was documented in a PRISMA flow diagram, and the characteristics of included studies were summarized in a table.

Data extraction and management

Data were extracted independently by pairs of authors using a standardized form capturing methods, participants, interventions, outcomes, and notable features. Disagreements were resolved through discussion or consultation with a third reviewer. Trial authors were contacted for missing data with at least two follow-up e-mails.

Assessment of risk of bias in included studies

The risk of bias was evaluated using version 2 of Cochrane’s Risk of Bias Assessment Tool (RoB 2) [12].

Measures of treatment effect

Dichotomous outcomes were reported as risk ratios (RRs) with 95% confidence intervals (CIs). Continuous outcomes were presented as mean differences (MDs) or standardized mean differences (SMDs) with 95% CIs.

Dealing with missing data

We contacted the original study authors to obtain missing data.

Assessment of heterogeneity

We assessed heterogeneity using the Chi² test and the I² statistic. Substantial heterogeneity (I² > 50%) was explored using prespecified subgroup analyses, such as comorbidities, frailty, and type of CGA team.

Data synthesis

We pooled data from at least two homogeneous studies using a fixed-effects model in Review Manager 5 software. A random-effects model was employed for heterogeneous data. We conducted meta-analysis for all-cause mortality and hospitalization outcomes. Other outcomes could not be meta-analyzed due to variations in instruments, reporting, and incomplete data.

Summary of findings and assessment of the certainty of the evidence

We created a Summary of Findings (SoF) table for two primary outcomes: all-cause mortality and hospitalization. We used GRADE approach to asses the certainty of evidence [13].

Results

Study selection

A summary of the search and selection of included studies is presented in PRISMA flowchart [9] (see Fig. 1). The systematic search was done on June 7th, 2022; we identified 11.037 studies and 388 articles, with 1.325 duplicate records removed automatically. We screened 10.100 studies manually and sought 82 reports for full-text assessment. Fifty-six articles were successfully retrieved and went through a rigorous full-text assessment, in which 37 studies were excluded for failing to meet the inclusion criteria. Finally, seven randomized critical trials were included in this review [14–20].

Fig. 1.

PRISMA Flowchart

Characteristics of included studies

We included seven RCTs [14–20] (Williams, 1987; Epstein, 1990; Schrijnemaekers, 1995; Boult, 2001; Cohen, 2002; Puts, 2018; and Paillaud, 2022) for further analysis and data extraction (see Table 1). Those seven articles amount to a total of 3,254 subjects undergoing CGA in the outpatient clinic. The articles had different cutoff points of age to define geriatric patients, including 65 years (2 articles), 70 years (4 articles), and 75 years of age (1 article). All studies included patiens with comorbidites or were rated frail. A geriatric assassement was conducted by a geriatrician in 6 of the 7 articles; only one article (Puts, 2018) did not report a specific assessor for CGA. Two articles (Epstein, 1990; and Boult, 2001) [15, 17] reported gerontological nurse as part of CGA team.

Table 1.

Characteristics of included articles

Study ID	N	Age		Included diagnosis	Intervention		Comparator	Relevant outcomes	FU*
		Min.	Avg.		Assessment	Treatment
Williams, 1987 [14]	150	65	76	Various self-reported comorbities.	A comprehensive assessment done by internists and family physicians specializing in geriatric.	Further treatment by the Geriatric Ambulatory Consultative Service (GACS) team.	Geriatric evaluation by a well-qualified general internist	Hospitalization Cost Satisfaction	12
Epstein, 1990 [15]	390	70	76.7	Were rated by the primary physician as having fair or worse health.	A 2 h geriatric assessment and examination by a geriatrician, geriatric nurse, and a social worker.	No information	Usual care	Mortality Hospitalization Cognitive Satisfaction Cost	12
Schrijne- maekers, 1995 [16]	222	75	NI	Physically vulnerable older patients	A comprehensive assessment by a geriatrician, psychologist, and social worker.	Assessment guided treatment by the General Practitioner.	Usual care	Mortality ADL IADL Cognitive	6
Boult, 2001 [17]	568	70	78.8	DM, Coronary artery disease, stroke, emphysema, arthritis, hip fracture	Assessment by a gerontological nurse practitioner and a geriatrician. Followed by a 15-minute discussion on intervention priorities.	Interdisciplinary primary care by the GEM team consisting of a social worker, gerontology nurse, and geriatrician.	Usual care by qualified physician	Mortality Cost	18
Cohen, 2002 [18]]	1388	65	74.2	Frail patient with a history of at least 2 days of hospitalization.	Assessment by a geriatrician, nurse, and social worker.	Treatment in a specified clinic for GEM bya team of social worker, nurse, and geriatrician	Usual care by clinic staff	Mortality ADL IADL QoL Cost	6 12
Puts, 2018 [19]	61	70	74.7	Undergoing at least 6 weeks of chemotherapy for stage 2–4 gastrointestinal, genitourinary, or breast cancer.	Geriatric assessment by a medical doctor and a registered nurse.	Integrated care by medical team.	Usual care by oncology team	Mortality IADL QoL	6
Paillaud, 2022 [20]	475	70	75.2	Head and neck cancer with other comorbidities.	Assessment by a senior geriatrician and a nurse.	No information	Usual care for head and neck cancer patient	Mortality ADL	24

*Follow-up time in months

Risk of bias assessment

A summary of the risk of bias assessment is included in Fig. 2. The mortality and hospitalization outcomes have risk of bias of low or some concern due to it being easier to define and record. Other outcomes (i.e., quality of life, satisfaction, functional status in daily living, cognitive function, ) leans heavily toward high-risk of bias due to the measurement process, which is highly subjective to the patient or the researcher.

Fig. 2.

Risk of bias of included studies classified to the outcomes

Outcomes

Mortality

Six studies reported all cause mortality (Epstein, 1990; Schrijnemaekers, 1995; Boult, 2001; Cohen, 2002; Puts, 2018; and Paillaud, 2022) [15–20]. All studies show no significant difference in mortality risk between the two groups, with pooled risk ratio (RR) of 1.04 (95%CI 0.88 to 1.23) see Fig. 3.

Fig. 3.

Forest plot showing the effect of outpatient CGA on the risk of mortality

Quality of life

We observed the effects of CGA on the patient’s quality of life in two studies (Cohen 2002 and Puts 2018) with a high risk of bias [18, 19]. A meta-analysis was not conducted because the two studies used different assessment tools. Cohen (2002) used the Short Form Survey-36 (SF-36) tool, while Puts (2018) applied the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) [18, 19]. Both tools assessed nine health domains on a scale of 0 to 100, but the domains differed in composition. Cohen (2002) reported a significant improvement in the mental health domain of the SF-36 for the outpatient CGA group after 12 months, with a mean score change of 5.7 compared to 1.5 in the usual care group (p < 0.01) [18]. Similarly, Puts (2018) found better quality-of-life scores for CGA patients after three months using the EORTC QLQ-C30, but this improvement was not significant after six months, likely due to loss of follow-up [19]. The adjusted score absolute difference between the groups at three months was 6.5 (95% CI: 9.6–22.7) [19].

Satisfaction

Williams (1987) and Epstein (1990) studied the impact of outpatient CGA on patient satisfaction [14, 15]. Williams (1987) exhibited some bias concerns, while Epstein (1990) had a high risk of bias. Both studies presented findings in a way that precluded meta-analysis, as Epstein (1990) only used a bar graph without detailed explanations. Neither study found significant differences in patient satisfaction between groups [14, 15]. Williams (1987) reported that 79% of CGA patients and 81% of control patients were satisfied with their evaluation and care plan [15].

Hospitalization

Williams (1987) and Epstein (1990) also investigated the effect of outpatient CGA on hospitalization rates [14, 15]. The meta-analysis of 507 hospitalizations showed no significant difference, with a risk ratio of 1.01 (95% CI: 0.77–1.32). Williams (1987) reported 26 hospital admissions in the CGA group compared to 23 in the control group over one year, but the total number of hospital days differed significantly, with 670 days for the CGA group and 1,113 days for the control group [14]. Similarly, Epstein (1990) found that the mean length of hospital stay was shorter in the CGA group (7.8 days) compared to the control group (9.3 days) [15] (Fig. 4).

Fig. 4.

Forest plot showing the effect of outpatient CGA on the risk of hospitalization

Functional status of basic activities in daily living

Five studies examined the impact of outpatient CGA on patients’ ADL scores. However, data from two studies (Shrijnemaekers, 1995 and Cohen, 2002) [16, 17] could not be included in a meta-analysis due to significant heterogeneity and high risk of bias. Additionally, one study (Paillaud, 2022) presented ADL outcomes as the proportion of patients experiencing a reduction of at least two points in their ADL score, which was similar between the CGA and usual care groups (41% vs. 38%) [20].

Two other studies (Williams, 1987 and Boult, 2001) assessed functional status using different tools. Williams, 1987 employed a Physical Assessment Form (PAF), but provided no detailed description of its components [14]. This study reported a 26.3% decrease in average function in the intervention group compared to the control group [14]. Conversely, Boult, 2001 utilized the Physical Function Domain of the Sickness Impact Profile (SIP: PFD) to measure functional status [17]. This study reported significant improvements favoring the CGA group at six months (SIP: PFD scores: 13.5 vs. 16.3), 12 months (14.8 vs. 18.4), and 18 months (15.7 vs. 18.9) [19].

Functional status of instrumental activities in daily living

Three studies (Shrijnemaekers, 1995; Cohen, 2002; and Puts, 2018) investigated the impact of outpatient CGA on changes in IADL [16, 18, 19]. Due to substantial heterogeneity and high risk of bias, the data could not be pooled [16, 18]. Notably, Puts, 2018 reported outcomes as the proportion of IADL impairment rather than IADL scores, further limiting comparability [19].

Cognitive

Two studies (Epstein, 1990 and Shrijnemaekers, 1995) evaluated the impact of outpatient CGA on patients’ cognitive function, but both were at high risk of bias [15, 16]. Meta-analysis was not feasible because Epstein, 1990 presented post-intervention cognitive scores only in bar graphs without detailed numerical data [15]. This study showed a significant improvement in cognitive function favoring the CGA group at three months but found no significant difference at 12 months [15]. Similarly, Shrijnemaekers, 1995 observed better cognitive scores in the CGA group, although the results were not statistically significant [16].

Cost

Four studies (Williams, 1987; Epstein, 1991; Boult, 2001; and Cohen, 2002) compared the cost of outpatient CGA to usual care [14, 15, 17, 18]. Variations in cost definitions and measurement methods made direct comparisons challenging. Results were mixed: two studies (Williams, 1987 and Cohen, 2022) favored CGA, while the others (Epstein, 1991 and Boult, 2001) favored usual care. Most findings were statistically insignificant, except for Boult, 2001, which identified significant cost differences favoring usual care during a subanalysis of the lowest spender quartile [15]. It is worth noting that healthcare utilization costs are often highly skewed, as exemplified in Williams, 1987, where 15% of patients accounted for 75% of the total cost [14].

Summary of findings and assessment of the certainty of the evidence

The summary of findings (SoF) table focuses on two primary outcomes: all-cause mortality and hospitalization (Table 2). The certainty of evidence for these outcomes was assessed using the GRADE approach.

Table 2.

Summary of findings and GRADE assassment

Outcomes	№ of participants (studies) Follow-up	Certainty of the evidence (GRADE)	Relative effect (95% CI)	Anticipated absolute effects
				Risk with Usual Care	Risk difference with CGA
All cause mortality (Mortality) follow-up: range 6 months to 18 months	3101 (6 RCTs)	⨁◯◯◯ Very lowa, b,c	RR 1.04 (0.88 to 1.23)	148 per 1,000	6 more per 1,000 (18 fewer to 34 more)
Hospitalization (Risk of Hospitalization) assessed with: Number of patient admission follow-up: mean 12 months	507 (2 RCTs)	⨁◯◯◯ Very lowd, e,f	RR 1.01 (0.77 to 1.32)	292 per 1,000	3 more per 1,000 (67 fewer to 93 more)
*The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: confidence interval; RR: risk ratio
GRADE Working Group grades of evidence
High certainty: we are very confident that the true effect lies close to that of the estimate of the effect.
Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect.
Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect.

Explanations

(a) There are three studies with high risk of bias and some concern in several aspects, including randomization, adhering to intervention, missing putcome data, measurement outcome, and selection report result (b) The results from all of 6 studies are inconsistent (c) The confidence interval includes the possibility that there is no difference between CGA and usual care (d) One studies shows some concern in adhereing of intervention (e) The result from two studies are inconsistent (f) The confidence interval includes the possibility that there is no difference between CGA and usual care

Discussion

Summary of main results

We included seven randomized clinical trials comparing comprehensive geriatric assessment (CGA) in hospital outpatient clinics to usual care. We aim to include all studies related to CGA without imposing limitations on the year of publication. CGA is a multidisciplinary, holistic evaluation of older adults that assesses medical, functional, cognitive, and social factors to create a coordinated care plan aimed at optimizing health outcomes. It is particularly beneficial for frail individuals with complex health issues, allowing for tailored interventions and improved management of comorbidities. In contrast, usual care typically involves standard medical assessments and treatments without the structured, comprehensive approach of CGA. Usual care may lack coordination among healthcare providers, potentially leading to fragmented care and missed opportunities for addressing multifaceted health needs. It often focuses on addressing acute medical issues or managing chronic diseases without a comprehensive evaluation of the patient’s broader needs. Usual care is typically delivered by a single healthcare provider and may not involve multidisciplinary collaboration or detailed assessments of functional or social factors. This approach can result in fragmented care and may overlook critical aspects of an older adult’s health.

These studies involved a total of 3,254 subjects, including work by Williams (1987), Epstein (1990), Schrijnemaekers (1995), Boult (2001), Cohen (2002), Puts (2018), and Paillaud (2022) [14–20]. Low-quality evidence revealed no significant differences in all-cause mortality, patient satisfaction, hospitalization rates, functional status (basic and instrumental activities of daily living), cognitive outcomes, or costs. Very low-quality evidence suggested improved quality of life in the CGA group at 3 and 12 months, as reported by Cohen (2002) and Puts (2018).

All studies reported no significant differences in hospitalization risk. This finding contrasts sharply with results from CGA administered during or after hospital admissions, which consistently reduce institutionalization rates [4, 21]. Similarly, CGA delivered through home visits or in primary care settings shows potential for reducing unplanned hospitalizations [22, 23]. The studies produced mixed results on functional and cost outcomes [14–20]. Regarding cognitive function, two studies slightly favored the CGA group, although results remained insignificant after 12 months [15, 16].

The four studies assessing costs found insignificant results, with two favoring CGA [14, 18] and two favoring usual care [15, 17]. A subanalysis by Boult (2001) revealed significant differences favoring usual care in the lowest-spending quartile [15]. This may reflect the higher initial costs of CGA, which decrease over time through reduced inpatient care costs, fewer outpatient visits, and lower medication use [24, 25]. Notably, all cost analyses included both outpatient and inpatient care costs, which might explain the variations in findings [14, 15, 17, 18].

Due to methodological limitations in the studies analyzed in this meta-analysis, the evidence presented in this journal is weak. Additionally, there is significant heterogeneity in CGA implementation, as different studies use varying assessment components and tools, particularly for frailty evaluation, which differs across hospitals and countries. This inconsistency makes it challenging to compare outcomes and draw definitive conclusions. There is a critical need for internationally standardized CGA protocols, particularly regarding the assessment of individual components, such as frailty status, which currently relies on varying tools across hospitals and countries. Establishing standardized protocols is essential to accurately determine the clinical efficacy of CGA. Nevertheless, integrated geriatric outpatient clinics (not explicitly incorporating CGA) significantly reduce prescribed medications and clinic visits [25]. This suggests that expanding patient access to geriatric outpatient services may yield greater benefits than focusing solely on in-depth CGA, especially in developing countries where geriatric outpatient service utilization remains limited [26].

Limitations of the evidence included in the review

The seven included studies highlight significant variability in CGA implementation across centers. These differences make it challenging to draw robust conclusions or compare results. CGA is a complex intervention that depends heavily on contextual factors, such as available resources, team composition, and assessment tools [27]. Establishing a standardized framework for CGA in hospital outpatient settings is crucial. Similar consensus guidelines already exist for CGA in primary care [28], emergency departments [29], and home care [30]. Furthermore, although the assessment of functional status utilizes the same tools, there are several studies with a high risk of bias, making it impossible to process the data into a high quality forest plot. Future research should follow standardized protocols tailored to outpatient settings to address these limitations.

Limitations of the review process

We conducted an extensive literature search across multiple databases using a broad search strategy, resulting in over 10,000 records. Two independent reviewers manually screened these records to ensure accuracy. However, the inherent complexity of CGA, including its varying names [27], team structures, and implementation strategies, may have caused some relevant studies to fall outside our inclusion criteria. We also excluded studies where CGA was conducted piecemeal across multiple clinical settings, even if one of those settings was a hospital outpatient clinic.

Agreements and disagreements with other studies or reviews

This systematic review is the first to focus exclusively on CGA in hospital outpatient settings. Despite rigorous methodology, the substantial variability in study designs made it difficult to draw definitive conclusions or conduct meta-analyses for several outcomes. Five of the eight evaluated outcomes—physical function, quality of life, satisfaction, and cost—were particularly prone to bias due to their subjective nature. Furthermore, the studies were limited to North America [14, 15, 17–19] and Europe [16, 20] restricting the generalizability of the findings to other regions, including developing countries.

Funding Declaration

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Conclusion

Implications for practice

Our review did not find sufficient evidence to support the benefits of outpatient CGA in terms of patient mortality, satisfaction, functional and cognitive status, or cost. As such, the findings currently have limited implications for clinical practice.

Implications for research

Future randomized controlled trials should aim to standardize CGA protocols in outpatient settings. Researchers should also consider studying CGA implemented in stages across multiple clinical settings, as this approach may yield more comprehensive insights into its effectiveness. Standardization and broader investigation will help address the variability and limitations observed in existing studies.

Appendix

Search strategy used for pubmed

1	(“aged” [MeSH Terms]) OR (“aged, 80 and over” [MeSH Terms]) OR (“frail elderly” [MeSH Terms])
2	(geriatr*[Title/Abstract]) OR (elder*[Title/Abstract]) OR (senior[Title/Abstract]) OR (gerontal [Title/Abstract]) OR (geratic [Title/Abstract]) OR (older [Title/Abstract]) OR (frail* [Title/Abstract])
3	(over 60 [Title/Abstract]) OR (over 65 [Title/Abstract]) OR (over 70 [Title/Abstract])
4	OR/1–3
5	(comprehensive [Title/Abstract]) OR (multidimension* [Title/Abstract]) OR (interdisciplin* [Title/Abstract]) OR (multidisciplin* [Title/Abstract])
6	(assessment [Title/Abstract]) OR (care [Title/Abstract]) OR (evaluation [Title/Abstract]) OR (services [Title/Abstract]) OR (management [Title/Abstract]) OR (treatment [Title/Abstract]) OR (intervention [Title/Abstract]) OR (function*[Title/Abstract])
7	(health services [Title/Abstract]) OR (health status [Title/Abstract])
8	OR/5–7
9	AND/1,8
10	(Geriatric Assessment [MeSH Terms]) OR (Health Services for the Aged [MeSH Terms]) OR (“Comprehensive Geriatric Assessment“[tw]) OR (“Comprehensive Geriatric Care“[tw]) OR (“Geriatric Evaluation and Management“[tw])
11	OR/9–10
12	(Outpatients[MeSH Terms]) OR (Outpatient Clinics, Hospital [MeSH Terms]) OR (Ambulatory Care [MeSH Terms]) OR (Ambulatory Care Facilities [MeSH Terms]) OR (outpatient*[Title/Abstract]) OR (ambulatory[Title/Abstract])
13	(“Quality of Life“[MeSH Terms]) OR (life quality[Title/Abstract]) OR (Quality of Life[Title/Abstract])
14	(Mortality [Mesh Terms]) OR (Mortality [Title/Abstract]) OR (Death [Title/Abstract]) OR (Fatality [Title/Abstract])
15	(Patient Satisfaction [MeSH Terms]) OR (((Patients [Title/Abstract]) OR (Client” [Title/Abstract]) OR (Consumer“[Title/Abstract])) AND ((Satisfaction [Title/Abstract] OR Experience [Title/Abstract])))
16	(Hospitalization [MeSH Terms]) OR (Institutionalization [MeSH Terms]) OR (Hospitalization [Title/Abstract]) OR (Institutionalization [Title/Abstract]) OR (Admission[Title/Abstract])
17	(Activities of Daily Living[MeSH Terms]) OR (Activities of Daily Living[Title/Abstract])
18	(costs and costs analysis[MeSH Terms]) OR (cost-benefit analysis[MeSH Terms])OR (economic evaluation[Title/Abstract]) OR (cost[Title/Abstract]) OR (ICER[Title/Abstract]) OR (“Incremental Net Benefit“[Title/Abstract])
19	OR/13–18
20	AND/11,12,19
21	(“child“[MeSH Terms]) OR (“young adult“[MeSH Terms]) OR (“adolescent“[MeSH Terms]) OR (“infant“[MeSH Terms])
22	20 NOT 21

Search strategy for proquest

((MESH(“Quality of Life”) OR AB, TI (“life quality” OR “Quality of Life”)) OR (MESH(Mortality) OR AB, TI (Mortality OR Death OR Fatality)) OR (MESH(Patient Satisfaction)OR(AB, TI(Patients OR Client* OR Consumer*) AND AB, TI (Satisfaction OR Experience))) OR (MESH(Hospitalization OR Institutionalization) OR AB, TI(Hospitalization OR Institutionalization OR Admission)) OR (MESH(“Activities of Daily Living”) OR AB, TI(“Activities of Daily Living”)) OR (MESH(“costs and cost analysis” OR “cost-benefit analysis”) OR AB, TI(“economic evaluation” OR cost OR ICER OR “Incremental Net Benefit”)))

Search strategy for EMBASE

#1	“’aged’/exp”
#2	“geriatr*:ab, ti OR ‘over 60’:ab, ti OR ‘over 65’:ab, ti OR ‘over 70’:ab, ti OR elder*:ab, ti OR senior: ab, ti OR gerontal: ab, ti OR geratic: ab, ti OR older: ab, ti OR frail*:ab, ti”
#3	“#1 OR #2”
#4	“comprehensive: ab, ti OR multidimension*:ab, ti OR interdisciplin*:ab, ti OR multidisciplin*:ab, ti OR assessment: ab, ti OR care: ab, ti OR evaluation: ab, ti OR services: ab, ti OR management: ab, ti OR treatment: ab, ti OR intervention: ab, ti OR function*:ab, ti OR ‘health services’:ab, ti OR ‘health status’:ab, ti”
#5	“#3 AND #4”
#6	“’geriatric assessment’/exp OR ‘elderly care’/exp”
#7	“’comprehensive geriatric assessment’:ab, ti OR ‘comprehensive geriatric care’:ab, ti OR ‘geriatric evaluation and management’:ab, ti”
#8	“#5 OR #6 OR #7”
#9	“’outpatient’/exp OR ‘outpatient care’/exp OR ‘outpatient department’/exp OR ‘ambulatory care’/exp OR outpatient*:ab, ti OR ambulatory: ab, ti”,526354,2 Jun 2022
#10	“#8 AND #9”
#11	“’randomized clinical trial’ OR ‘controlled clinical study’ OR random*:ab, ti OR randomization OR ‘intermethod comparison’ OR placebo: ab, ti OR compare: ti OR compared: ti OR comparison: ti OR ((evaluated: ab OR evaluate: ab OR evaluating: ab OR assessed: ab OR assess: ab) AND (compare: ab OR compared: ab OR comparing: ab OR comparison: ab)) OR ‘open adj label’:ab, ti OR (((double OR single OR doubly OR singly) NEXT/1 (blind OR blinded OR blindly)): ab, ti) OR ‘double blind procedure’ OR ‘parallel group*’:ab, ti OR crossover: ab, ti OR ‘cross over’:ab, ti OR (((assign* OR match OR matched OR allocation) NEXT/5 (alternate OR group* OR intervention* OR patient* OR subject* OR participant$)):ab, ti) OR assigned: ab, ti OR allocated: ab, ti OR ((controlled NEXT/7 (study OR design OR trial)): ab, ti) OR volunteer: ab, ti OR volunteers: ab, ti OR ‘human experiment’ OR trial: ti”
#12	“((random* NEXT/1 sampl* NEXT/7 (‘cross section*’ OR questionnaire* OR survey* OR database*)):ab, ti) NOT (‘comparative study’:ab, ti OR ‘controlled study’:ab, ti OR ‘randomi*ed controlled’:ab, ti OR ‘randomly assigned’:ab, ti OR (‘cross-sectional study’:ab, ti NOT (‘randomized controlled trial’:ab, ti OR ‘controlled clinical study’:ab, ti OR ‘controlled study’:ab, ti OR ‘randomi*ed controlled’:ab, ti OR ‘control group*’:ab, ti))) OR (((case NEXT/1 control*):ab, ti) AND random*:ab, ti NOT randomi*ed: ab, ti AND controlled: ab, ti) OR (systematic: ti AND review: ti NOT (trial: ti OR study: ti)) OR (nonrandom*:ab, ti NOT random*:ab, ti) OR ‘random field*’:ab, ti OR ((‘random cluster’ NEXT/3 sampl*):ab, ti) OR (review: ab AND review: pt NOT trial: ti) OR (‘we searched’:ab AND (review: ti OR review: pt)) OR ‘update review’:ab OR ((databases NEXT/4 searched): ab) OR ((rat: ti OR rats: ti OR mouse: ti OR mice: ti OR swine: ti OR porcine: ti OR murine: ti OR sheep: ti OR lambs: ti OR pigs: ti OR piglets: ti OR rabbit: ti OR rabbits: ti OR cat: ti OR cats: ti OR dog: ti OR dogs: ti OR cattle: ti OR bovine: ti OR monkey: ti OR monkeys: ti OR trout: ti OR marmoset*:ti) AND ‘animal experiment’) OR (‘animal experiment’ NOT (‘human experiment’ OR ‘human’))”
#13	“#10 AND #11 NOT #12”
#14	“’quality of life’/exp”
#15	“’all cause mortality’/exp OR ‘standardized mortality ratio’/exp”
#16	“’patient satisfaction’/exp OR (((patients OR client OR consumer) NEXT/1 (satisfaction OR experience)): ab, ti)”
#17	“’hospitalization’/exp OR ‘institutionalization’/exp”
#18	“’daily life activity’/exp OR ‘activities of daily living’:ab, ti OR ‘adl disability’/exp”
#19	“’cost minimization analysis’/exp OR ‘cost benefit analysis’/exp OR ‘cost effectiveness analysis’/exp OR ‘cost utility analysis’/exp”
#20	“#14 OR #15 OR #16 OR #17 OR #18 OR #19”
#21	“#13 AND #20”
#22	“#21 AND [embase]/lim”

Electronic supplementary material

Below is the link to the electronic supplementary material.

Abbreviations

ADL

Activity of Daily Living

CGA

Comprehensive Geriatric Assessment

CI

Confidence Intervals

DM

Diabetes Mellitus

EORTC QLQ

European Organization for Research and Treatment of Cancer Quality of Life Questionnaire

GACS

Geriatric Ambulatory Consultative Service

GEM

Geriatric Emergency Medicine

HAS

Home Assessment Service

HHAS

Hospital Home Assessment Service

IADL

The Lawton Instrumental Activities of Daily Living Scale

ICTRP

International Clinical Trials Registry Platform

OAS

Outpatient Assessment Service

PAF

Physical Assessment Form

PROSPERO

International Prospective Register of Systematic Reviews

QoL

Quality of Life

RCT

Randomized controlled trials

RoB

Risk of Bias

RR

Risk Ratio

SIP:PFD

Physical Function Domain of the Sickness Impact Profile

SMD

Standardized Mean Differences

SoF

Summary of Findings

Author contributions

Substantial contributions to the conception: EDS, RR, SS, SRFS, RI, WW, NKP, JM Design of the work: EDS, NKP, RR, SS, SRFS, WW Acquisition, Analysis Interpretation of Data: EDS, NKP, RR, SS, SRFS, RI, MKA, JM, RAS, WW Draft and revised: EDS, NKP, RR, SS, KH, JM All authors reviewed the manuscript.

Funding

The authors did not receive any funding in this study.

Data availability

All the data and materials needed are already provided in the manuscript.

Declarations

Ethical approval

The ethics approval is not applicable in this type of study.

Consent for publication

This systematic review does not include any human subjects therefore consent to participate in this study is not applicable. Human Ethics and Consent to Participate declarations are also not applicable. Clinical trial number also not applicable as this is a systematic review type of study.

Competing interests

The authors declare no competing interests.